Selecting a USRP Device - Ettus Knowledge Base

Application Note Number

AN-881

Highmesh supply professional and honest service.

Revision History

Date Author Details -05-01 Neel Pandeya
Nate Temple Initial creation -03-26 Nate Temple Update

Abstract

This AN explores the USRP family at a high level, compares devices across several primary features, and walks the reader through the process of selecting a particular device for the their application.

USRP Product Selector

The USRP Product Selector will help you choose the Ettus Research USRP Software Defined Radio products that are the best fit for your application. Based on your answers to a series of questions, the USRP Product Selector will generate a PDF price quote and it to you. The Ettus Research sales team may follow up with you to answer any additional questions that you might have. If you would like a person to talk you through the USRP product selection process, please send an to .

Overview

This guide is provided by Ettus Research to help users select the most appropriate Universal Software Radio Peripheral (USRP™) for their specific application. In order to make the selection process as straightforward as possible, a table showing various features is provided as a basis for the selection process.

Understanding DSP Fundamentals

If you are new to the USRP family of products, software defined radio, or digital signal processing in general, it may be useful to perform some simulation of the signals you wish to manipulate before selecting USRP hardware. Simulating signals and algorithms in software frameworks such as GNU Radio or LabVIEW will ensure a proper understanding of various concepts, such as Nyquist theorem, ADC/DAC and limitations, for example. Understanding the basics of signal theory and digital signal processing is the first step towards understanding how to make the best use of an appropriate USRP model. The Suggested Reading page provides access to several resources that may be helpful in understanding the basics.

Common Applications

Table 1 shows USRP/daughterboard combinations commonly used in various application areas. While Table 1 can serve as a starting point for selecting a USRP device, Ettus Research recommends new users evaluate their application requirements against the specifications of the USRP devices. sections of this document will assist in the selection process.

Application Area Common USRP Model Common Daughterboard PHY/MAC Research N200/N210 X300/X310 N300/N WBX/SBX/UBX/CBX Radar Research X300/X310 SBX/UBX OpenBTS B200/B X300/X310 E310/E N200/N210 N300/N E WBX/SBX/UBX/CBX Amarisoft LTE N200/N210 X300/X310 B E N300/N WBX/SBX/UBX/CBX Education B200/B X300/X310 E310/E N200/N210 N300/N E WBX/SBX/CBX/UBX HF Communications N200/N210 X300/X310 LFRX/LFTX Signals Intelligence X300/X310 N300/N E SBX/UBX Distributed RF Sensors E310/E312 N300/N310 E320 N/A Mobile Radios E310/E312 E320 N/A MIMO X300/X310 N SBX/UBX Phased Array X300/X310 SBX/UBX FPGA Computing X310 N E WBX/SBX/UBX/CBX Embedded Computing E310/E312 E320 N/A Small Form Factor (SWaP) B200mini/B205mini E310/E312 E320 N/A Table 1 - Recommended USRP Selection for Various Application Areas
1 - The B2xx, E3xx and N3xx do not support swappable daughterboards

USRP Device Characteristics

Table 2 shows the key characteristics of all USRP models available from Ettus Research. The table is useful for determining the interface type, bandwidth capabilities, and synchronization mechanisms specified for each USRP model. You can use this information, and the requirements for the application in question, to select a USRP radio.

USRP Model Interface Total Host BW (MSPS 16b/8b) Daughterboard Slots ADC Resolution (bits) ADC Rate (MSPS) DAC Resolution (bits) DAC Rate (MSPS) MIMO Capable Internal GPS Disciplined Oscillator (Optional) 1 PPS/Ref Inputs N210 GigE 25/50 1 14 100 16 400 Yes Yes Yes N200 GigE 25/50 1 14 100 16 400 Yes Yes Yes N300 1 GigE

10 GigE

153.6, 125, 122.88 2 16 153.6, 125, 122.88 14 153.6, 125, 122.88 Yes Yes Yes N310 1 GigE

10 GigE

153.6, 125, 122.88 2 16 153.6, 125, 122.88 14 153.6, 125, 122.88 Yes Yes Yes B200mini USB 3.0 61.44 N/A 12 61.44 12 61.44 No No Yes B205mini USB 3.0 61.44 N/A 12 61.44 12 61.44 No No Yes B200 USB 3.0 61.44 N/A 12 61.44 12 61.44 No Yes Yes B210 USB 3.0 61.44 N/A 12 61.44 12 61.44 Yes Yes Yes X300 USB 3.0

1 GigE

10 GigE

PCIe

200 2 14 200 16 800 Yes Yes Yes X310 USB 3.0

1 GigE

10 GigE

PCIe

200 2 14 200 16 800 Yes Yes Yes E310 Embedded 61.44 N/A 12 61.44 12 61.44 Yes No Yes E312 Embedded 61.44 N/A 12 61.44 12 61.44 Yes No Yes E320 Embedded

1 GigE

10 GigE

61.44 N/A 12 61.44 12 61.44 Yes Yes Yes Table 2 - USRP Characteristics by Model

The following sections cover frequently asked questions in choosing a USRP device that’s right for your application.

Do I want to perform processing on a host PC, or operate the USRP device in a standalone fashion?

This is an obvious differentiator of the USRP Embedded Series. If you need the USRP to operate a USRP radio without a host PC, the USRP E310/E312/E320 is the most appropriate. The USRP E310/E312/E320 is ideal for applications that might require mobile transceivers or distributed RF sensors. Unless the user has a clear requirement for embedded operation, Ettus Research recommends the USRP N200, N210, B200, B210, X300, X310, N300 or N310. Developing with a host-based platform typically involves less risk and will require less effort to optimize various pieces of the software radio.

In many cases it may be easier to develop with a USRP B200/B210 or USRP N200/N210, then port the code to the USRP E310/E312/E320. The UHD (USRP Hardware Driver) enables this portability. You must also consider the different processing capabilities of the host machine and ARM processor used on the USRP E310/E312/E320.

Do I Need Synchronization and/or MIMO Capability?

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Contact us to discuss your requirements of USRP For Sale. Our experienced sales team can help you identify the options that best suit your needs.

Table 3 summarizes the synchronization features of each USRP device. Table 4 shows recommended solutions for MIMO systems of various sizes.

If you need MIMO capability for your application, Ettus Research recommends the USRP N200/N210, X300/X310, N300/N310 or E320. These units can be synchronized by providing a common time and frequency reference. Two USRP N200/N210s can be synchronized for MIMO operation with an Ettus Research MIMO cable. Alternatively, external 10 MHz reference and 1 PPS signals can be distributed to multiple USRP radios. With proper consideration for interface issues, it is possible to create MIMO system of arbitrary size with the USRP N200/N210, X300/X310, N300/N310 and E320.

The USRP B210, N300, E310/E312/E320 can serve a 2x2 MIMO capability because it has two integrated RF channels. When using the USRP B210 the available bandwidth is limited dependent upon the USB controller, and selected MIMO configuration. The USRP E310/E312's streaming bandwidth is limited to the 1 GigE interface to the ARM CPU. The USRP E320 supports streaming at full rate of 61.44 MS/s (SISO) or 30.72 MS/s (MIMO) via the 10 Gb interface. The USRP N300 supports streaming at 153.6 MS/s (SISO) and 125 MS/s (MIMO) via the 10Gb interface.

USRP Model BW Capability (MSPS w/ 16-bit) MIMO Capable Ext Ref. Input 1 PPS Input Internal GPS Disciplined Oscillator (Optional) Plug and Play MIMO N200 25 X X X X X N210 25 X X X X X N300 153.6, 125, 122.88 X X X X X N310 153.6, 125, 122.88 X X X X X B200mini 61.44 X X B205mini 61.44 X X B200 61.44 X X X B210 61.44 X X X X X X300 200 X X X X X X310 200 X X X X X E310 61.44 X X X X E312 61.44 X X X X E320 61.44 X X X X X Table 3 - Synchronization Capability of USRP Devices USRP Model 2 x 2 MIMO 4 x 4 MIMO M x N MIMO N200/N210 MIMO Cable OctoClock OctoClock N300 Integrated Octoclock, White Rabbit Octoclock, White Rabbit N310 Integrated Integrated Octoclock, White Rabbit B200mini Not Recommended (SISO Only) Not Recommended Not Recommended B205mini Not Recommended (SISO Only) Not Recommended Not Recommended B200 Not Recommended (SISO Only) Not Recommended Not Recommended B210 Integrated Not Recommended Not Recommended X300 Integrated with Dual Daughterboards OctoClock OctoClock X310 Integrated with Dual Daughterboards OctoClock OctoClock E310 Integrated Not Recommended Not Recommended E312 Integrated Not Recommended Not Recommended E320 Integrated Octoclock Octoclock Table 4 - Recommended Models for MIMO Systems

What Are My Bandwidth Requirements?

Many Bandwidth requirements can also be used to narrow down the USRP selection. As seen in the table, the USRP N200/N210 is capable of streaming up to 50 MS/s in each direction in 8-bit mode, and 25 MS/s in 16-bit mode. The USRP B200 is capable of streaming up to 61.44MS/s total in 16-bit, 12-bit or 8-bit modes. The USRP E320 is capable of streaming up to 61.44 MS/s in 16-bit mode. The X300/X310 is capable of streaming up to 200 MS/s per channel (400 MS/s total) with 160 MHz of usable bandwidth per channel. The N300/N310 is capable of streaming up 122.88, 125 or 153.6 MS/s per channel. The N300/N310 is limited to 2x2 operation when using a 153.6 MS/s sample rate.

However, if there is interest in transmit and/or receiving larger bandwidth signals such as 802.11, the USRP N200/N210, X300/X310, N300/N310 or E320 would be appropriate. Note these limitations are based on the data throughput provided by the corresponding interfaces. It is important to consider the performance of the processing platform, and the computational intensity of the application. The constraints of the processing platform are independent of the full capability of the Ettus Research USRP radio and UHD.

What interface do I prefer to work with?

Assuming you have narrowed the viable devices down based on bandwidth, MIMO and channel count requirements, it is possible to select a USRP device based on the interface.

In general, USB 3.0 ports are more plentiful on computers. This makes the USRP B200/B210/B200mini/B205mini slightly more usable at short ranges. The USRP N200/N210 requires a Gigabit Ethernet port and a PC typically only provides one such port. If internet access is required, the user will also need to plan for an additional network adapter. The USRP X300/X310, N300/N310 and USRP E320 all support streaming via either a 1 GigE or 10 GigE interface.

The Gigabit Ethernet interface of the USRP N200/N210 can operate over significantly longer ranges (typically up to 100ft) compared to the USB interface of the USRP B2xx. This makes it possible to operate the USRP radio it more remote locations further from the host computer. The GigE interface can be accessed via a Gigabit Ethernet switch, allowing access to multiple devices. However, Ettus Research recommends a homogeneous network without other devices, such as network routers attached.

The 10 Gigabit Ethernet interfaces of the USRP N300/N310, X300/X310 and E320 can be operated using multimode fiber optic cables with appropriate adapters which increases the distance from the host computer.

Will I develop custom IP for the USRP device’s FPGA?

While most users deploy their USRP devices in a stock configuration, many others customize the FPGA with their own functionality. For example, you may want to offload modulation, demodulation, or other PHY/ MAC operations to the FPGA. This reduces host processing requirements, and may allow data reduction before passing data over the host interface. A summary of the FPGAs used on each USRP model are shown in Table 5.

Model FPGA Vendor FPGA Series FPGA Part Number System Gates Logic Elements Logic Cells Slices DSP48's BRAM DCM's Free Tools? N200 Xilinx Spartan 3A DSP XC3SDA k - 37,440 16,640 84 260k 8 Yes N210 Xilinx Spartan 3A DSP XC3SDA k - 53,714 23,872 126 373k 8 No B200mini Xilinx Spartan-6 XC6SLX75 - - 74,637 93,296 132 3,096k 12 Yes B205mini Xilinx Spartan-6 XC6SLX150 - - 147,443 184,304 180 4,824k 12 No B200 Xilinx Spartan 6 XC6SLX75 - - 74,637 93,296 132 3,096k 12 Yes B210 Xilinx Spartan 6 XC6SLX150 - - 147,443 184,304 180 4,824k 12 No X300 Xilinx Kintex-7 XC7K325T - - 321k 407,600 840 16,020k - No X310 Xilinx Kintex-7 XC7K410T - - 406k 508,400 28,620k - No E310 Xilinx Zynq- XC7Z020 - - 85k 106,400 220 560k - Yes E312 Xilinx Zynq- XC7Z020 - - 85k 106,400 220 560k - Yes E320 Xilinx Zynq- XC7Z045 - - 350k 437,200 900 19.2 Mb - No N300 Xilinx Zynq- XC7Z035 - - 275k 343,800 900 17.6 Mb - No N310 Xilinx Zynq- XC7Z100 - - 444K 554,800 26.5 Mb - No Table 5 - FPGA Resources

The USRP N200 and USRP N210 are great, generic platforms to experiment with FPGA development. However, the important difference between these two is the FPGA size, and requirements for Xilinx development tools. The USRP N200 includes a Xilinx Spartan XC3SDA FPGA. This FPGA is optimized for DSP capability, and the logic can be modified with free Xilinx ISE tools. The USRP N210 includes a Xilinx Spartan XC3DA FPGA. This FPGA provides nearly twice the resources, but requires a licensed seat of the Xilinx development tools for development.

Do I need flexible sample clock frequencies?

Some applications may benefit from a flexible sample clock frequency. The USRP E310/E312/E320 and USRP B200/B210/B200mini/B205mini include a flexible frequency clocking solution. This flexibility allows ideal sample clock frequencies to be used for various communications standards. For example, the GSM implementations commonly use a 52 MHz sample clock.

Do I want or need a rack-mountable solution?

Generally speaking, the selection of the USRP is based on performance requirements of the electrical components. However, the convenience of a rack-mounted solution may be an attractive feature that drives your decision. The USRP N200/N210, X300/X310 and N300/N310 can all be mounted in Ettus Research rack chassis. Up to four N200/N210 USRP devices can be mounted in the 3U chassis. Up to two X300/X310 or N300/N310 USRP devices can be mounted in the 1U chassis.

Will my requirements become more demanding as I learn more about the USRP and RF systems?

One final thing to consider is how your requirements will change over time. While a lower-cost USRP device, such as the USRP B200/B200mini, may meet your immediate requirements, it is possible that the USRP N200/N210, N300/N310 or E320 would be a more appropriate platform as you continue to develop more advanced RF systems. Key improvements to note in the higher-end USRP N200/N210/X300/X310/N300/N310/E320 is the increased bandwidth, increased dynamic range, and MIMO capability.

Fortunately, UHD allows the user to develop a single application compatible with all USRP models. Within certain limitations, the code you develop to work on a USRP B2xx will generally work on any other USRP. You must still consider variables such as sample rate, host interface bandwidth, and synchronization features to ensure compatibility.

Want more information on USRP for 5G Prototyping? Feel free to contact us.

Conclusion

Over the last few years I have seriously been bitten by the SDR bug. I currently use numerous RTL dongles for VHF and above searching, as UniTrunker receivers, etc. I also use an RF-Space SDR-IQ for shortwave listening. The more I use them the more I wonder if I ever want to return to a conventional type scanner or receiver.

With that in mind, I am looking at the Ettus Research USRP Instant SDR Kit:

https://www.ettus.com/product/details/UB100D-BDL

Does anyone here have experience with this or any USRP devices that can comment on performance. The above kit is priced at $675.00. Obviously the price goes up from there. While I expect more robust performance out of this as compared to that of an RTL dongle, my main question is just how much more performance will there be given the wide front end of these devices?

Also, I am at best a fledgling Linux user. To be honest I look at GNU Radio and it makes my head spin. Not being a programmer it makes me wonder if having this device and not having the software knowledge is going to make this come up short for me. I know I can get it working with SDR#.

There are other alternatives that exist or will soon exist. BladeRF is one but coverage starts at 300 MHz which is not acceptable to me. HackRF is coming as well but I'm thinking its specs don't live up to those of the USRP's. Airspy looks interesting but may just be a super-souped-up RTL dongle.

Any input on anyone's experience with using USRP devices, especially the above referenced one, would be greatly appreciated.

Thanks and Happy New Year!

Does anyone here have experience with this or any USRP devices that can comment on performance.

I have a USRP1 with several daughterboards (WBX and LFTX/LFRX) which gives coverage from DC up to frequencies higher than I've ever played with. Also have a HackRF board.

As to your general question about the USRP line, I can recommend it highly, but the ultimate answer of course would be based on what you want to do and how well that matches the various offerings available, of which more and more are coming online all the time. In particular, if you intend to only do RX and not TX, you would be paying for a USRP TX capability that would not be used...

I've personally met Matt Ettus and several other team members, and that's one reason why I give them a high recommendation. I'd buy from them again.

73

Max Hi Max,

Thanks for the input. I would be using the USRP for receive primarily, but I am a licensed amateur so I suppose having the TX functions could eventually be of interest. My primary use of it would be to be able to view a wide chunk of spectrum in the VHF/UHF ranges for signals and to be able to tune to a viewed signal immediately, as I can currently do with the RTL dongles which are of course limited to 2 MHz. I am primarily looking for such a setup that is more robust and will allow wider spectral viewing.

I'd be interested to know how the HackRF compares performance wise with your USRP as it appears I'd be using the same WBX daughterboard.

Again, thanks.

I'd be interested to know how the HackRF compares performance wise with your USRP as it appears I'd be using the same WBX daughterboard.

Have not used the HackRF as much as the USRP. The HackRF that I have was from an early beta test program, and some of these had soldering defects. One difference vs. the USRP is that the latter will run FDX, whereas the HackRF cannot TX and RX at the same time. Also the USRP supports MIMO directly, something that might be do-able with the HackRF DIY, if you use multiple boards and synchronize the clocks.

At the moment the vast bulk of my use of HackRF is using the TX side to generate test P25 trunking signals in the 900 MHz band. It's been pretty stable. One thing to note on the HackRF is it didn't work very well until I upgraded to the latest firmware...

Max Thanks. Are you operating primarily in a Linux environment? I need to learn GNU Radio's basics, and I suppose I should take the time to do so as I understand there is support for the RTL dongles. This is how little I know about it, unfortunately, and I anticipate at least in the early stages of having a USRP I'd be using Windows apps like SDR# and/or HDSDR.

My other main concern is that obviously when looking at a wide chunk of spectrum I may suffer from spurs, images, etc. I expect that USRP would be rather superior to the dongles in this regard, but just how much more superior. Sometimes just looking at 2 MHz or so is fine, but there are times when viewing a wider area will be something I want to do.

I appreciate your time; thanks again.

Thanks. Are you operating primarily in a Linux environment? I need to learn GNU Radio's basics, and I suppose I should take the time to do so as I understand there is support for the RTL dongles. This is how little I know about it, unfortunately, and I anticipate at least in the early stages of having a USRP I'd be using Windows apps like SDR# and/or HDSDR.

My other main concern is that obviously when looking at a wide chunk of spectrum I may suffer from spurs, images, etc. I expect that USRP would be rather superior to the dongles in this regard, but just how much more superior. Sometimes just looking at 2 MHz or so is fine, but there are times when viewing a wider area will be something I want to do.

I appreciate your time; thanks again.

yeah, I use Linux and GNURadio exclusively. One other thing about the HackRF is with its 20MHz sampling rate I can view the entire FM broadcast band in an FFT. The USRP1 can't sample that fast.

As for birdies, spurs, and all the rest, your results will vary especially if you're in an RF-dense environment. There are not many situations in RF where more filtering is a bad thing, and SDR receivers are no exception. I've got a RS PRO- scanner that is almost totally deaf on VHF due to intermod, a lot of which goes away by adding an inline FM trap. The same sorts of issues affect all receivers, and SDR isn't unique in this respect...

Max I had a USRP1 and currently use a USRP N210 with several daughter boards including the WBX. I find them to be remarkable devices. It's interesting capturing very large chunks of spectrum at a time.

The small dongles are fun but the USRP is a serious piece of gear compared to them.

I'm primarily into SDR these days having sold off my other receivers some years ago. I had an Icom R and a AOR R+3 and an Icom R75.

For HF I primarily use an HPSDR Hermes board and use the USRP for everything above.

The only thing I need is more time to tinker these days.

The B200/B210 devices look great but you may want to contact Ettus regarding them and the USB3 chipset in the computer you're using if you decide to go that direction. Apparently some chipsets have compatibility issues.

I had a USRP1 and currently use a USRP N210 with several daughter boards including the WBX. I find them to be remarkable devices. It's interesting capturing very large chunks of spectrum at a time.

The small dongles are fun but the USRP is a serious piece of gear compared to them.

That I'm glad to hear....I HOPE it is given the price!

I'm primarily into SDR these days having sold off my other receivers some years ago. I had an Icom R and a AOR R+3 and an Icom R75.

That's the direction I'm headed in as well. I sadly parted with the AOR ARA+3 that sat here for years with moving into the future in mind.

The B200/B210 devices look great but you may want to contact Ettus regarding them and the USB3 chipset in the computer you're using if you decide to go that direction. Apparently some chipsets have compatibility issues.

I will do that, thanks, I would not have known otherwise. I'm a little concerned about the lack of case, but I know there are options and I'll consider it. I obviously want to get the most bang for the buck, but I have to balance that with common sense as well. I know some physical mods have to be made to the third party cases; I probably don't have the right tools for the job so finding someone that does and will either help me or loan them is inevitable.

Thanks much for the input! My problem is that my knowledge of Linux is at best fledgling. I've installed Ubuntu 13.10 on my secondary computer and I'm dual booting with Windows 7. I managed to get GNURadio installed on it in the hopes of learning about it by using the RTL dongle that's attached. Of course getting the RTL dongle to work in Linux is my current challenge. I'm on the OsmoSDR site trying to figure that out. It appears that all of this is a steep learning curve and I'm willing to work towards it certainly, but I also require some Windows connectivity.

I would very happily forever run a USRP in SDR#, but I know it can do much more so that creates a conundrum for me. Given that I will use the USRP pretty much exclusively for simple visual searches of various amounts of radio spectrum, is it going to be worth it for me to struggle through the learning curve of Linux and GNUradio. One part of me wants to do so, but gradually and without pressure. That's why the other part of me needs this to work well in Windows. From what I read I think it will.

... but USB3 and up to 56 MHz of bandwidth seems pretty nifty.

What's the max you can look at for bandwidth with the USRP1 and WBX daughterboard? Am I correct in that about 16 MHz might be it?

Gig Ethernet is the way to go, supports remote access and the box will only have it IF it NEEDS it (unless it is poorly designed, (rare), or partially overspeced).

To answer your question: Ettus Research - Support: Knowledge Base , there are 'three parts' to the 'Black Box' (much like your Computer) where "Bandwidth" comes into play, if you skimp in one area you get a (you know this word) bottleneck (same as in your Computer); so choose each individual Component to match your intended use.

The USRP1's WBX has a 40 Mhz bandwidth, the ADC can digitize at 64 MS/s, and the USB 2.0 Interface does 8 MS/s (Half Duplex). That means a sweep of that bandwidth with so slow an ADC will make for a slow sweep time, hope you do not retrieve much Data (and you WILL) since you need to shove your 'answer' through USB 2.0 .

The USRP1 would be overkill if DSD is all it will ever be used for and likely unsatisfying IF you later get serious about the Hobby.

IE: I would buy one of the USB 3.0 Devices instead of a USB 2.0 Device, just because the USB 3.0 Interface is EIGHT times faster (and thus somewhat useful). Even a 100M Ethernet Device will be somewhat futureproof (for you, I presume, (too much?)), since you may not want a 1GE Box, and the massive expense of pro equipment.


Note: The actual streaming performance will depend on the processing capability of the host computer, the complexity of the application/DSP, and other factors.

Waiting always brings better stuff for less: http://avnetexpress.avnet.com/conte...s/Avnet ZedBoard Brochure English Version.pdf . The Mfg (Ettus) even suggests that the USRP1 is outdated and recommend a newer model. For the price of their other Model you can get this: http://www.zedboard.org/product/zynq-sdr-ii-eval (or any number of other newer Devices from various places). OTOH Ettus is much cheaper than NI (who makes their stuff and seems to have similar Devices for a much higher price). Also see:

Application Note - Selecting a USRP Device - Ettus Research
http://www.ettus.com/content/files/kb/application_note_selecting_a_usrp.pdf

The ZedBoard Series uses a newer and more powerful FPGA, and costs less
http://www.zedboard.org/buy

There are many NEW Boards with fancy Radios and FPGAs, so ZedBoard is not the only choice. Google for the newest Chips from the biggest Mfgs. and see who is making a Board that uses them.


To decide what you want (can afford) just Spec. it like a Computer:

1. IF you want an FPGA-Based System choose the FPGA you can afford (and might want to program, someday). Without one you NEED a fast i7.
2. Decide on a board with or without FMC Connectors (FMC allows upgrading Radio, or swapping perfectly good Radio to a newer, better FPGA)
3. A second General Purpose Processor (x86 or ARM) enables standalone operation, otherwise you MUST hook it up to your Computer, or turn it off.
4. If you are choosing an expensive FPGA and Radio (along with a uP) you might as well choose quality parts with really great Specs. in the Radio.
5. If it has an FPGA you probably want Ethernet and are unlikely to get by with USB 3.0 .
6. IF you have a SPECIFIC use you can focus on spending your money in one area (FPGA or Radio).
7 You don't NEED an FPGA or a Radio or to spend that much. Just use a Disc. Tap on your Scanner and buy a second Laptop to run 24/7, for a 'cheap' solution.

There IS a reason why some of the Gear is expensive, and people pay for it -- you may not share those reasons. Super Gear can be had for less than U$8K, really super cheap Gear (SDR USB Stick) can be had for less than $15 and it WILL provide over U$100 worth of enjoyment (as you already know).